Story highlights

If found guilty, the researcher faces up to 20 years in prison and a $1 million fine

Ames, Iowa (CNN)If government prosecutors are right, a former top researcher at Iowa State University is guilty of brazen scientific fraud-actions which a criminal complaint says have cost taxpayers nearly $15 million.

An indictment brought against Han says he falsely showed that rabbits infected with the virus had shown remarkable improvement. That improvement was so advanced that the government's National Institutes of Health awarded Iowa State and Han nearly $15 million in federal research grants.

Prosecutors say the false results actually cleared a first level of back-up testing but fell apart after Han's boss at Iowa State began to get suspicious.

According to the criminal complaint, the false results were secretly given to the NIH as well as a senior scientist at Iowa State after the first publication of the scientific paper. It was then, according to the complaint, that they discovered the rabbit blood was spiked with human antibodies, making it appear the rabbits were developing an immunity to the virus.

Read More

A spokesman for Iowa State University, John McCaroll, told CNN that the school's reaction was "disbelief, surprise, shock, disappointment."

In a letter attached to the complaint, and before he entered a plea of not guilty, Han said he was "foolish, coward and not frank." He added, "My misconduct is not done in order to hurt someone."

The U.S. attorney for the southern district of Iowa, Nicholas Kleinfeldt, told CNN that "just because somebody has a PhD, just because someone's involved in the scientific community, doesn't mean they're going to necessarily be treated differently than anyone else who's committed a criminal offense."

As for the roughly $15 million in federal research grants handed out to Han and Iowa State, most of it is gone, spent on salaries and lab gear, the spokesman said. The school did repay about $500,000.

According to Retraction Watch, a group that tracks research fraud, scientists who fake research rarely go to prison and hardly ever are forced to pay taxpayers back for misused grants.

In all, says a prominent scientist, the NIH has given about $58 million in funds to science that turned out to be phony over the past 22 years. Dr. Ferric Fang, a scientist at the University of Washington, added up the numbers but cautioned the real number may be even higher.

As for Han, there was no answer at a Cleveland apartment building where he was believed to be staying until the trial. CNN did reach him on his cell phone, and when asked what happened, time and again he said only two words: "I'm sorry."

If he's found guilty on all the four federal charges against him, prosecutors say he faces up to 20 years in prison and a $1 million fine.